Wasmtime GitHub notifications bot (Mar 03 2026 at 18:01): Wasmtime GitHub notifications bot (Mar 03 2026 at 18:01):saulecabrera opened PR #12708 from saulecabrera:winch-improve-addressing-modes to bytecodealliance:main:
Prior to this commit, Winch's
Addressrepresentation relied on the general(reg, offset)form for offset-based addressing, leaving the materialization of the addressing mode to Cranelift. This approach led to the following bug found by the fuzzer:When offsets cannot be encoded as a 9-bit signed immediate offset or a 12-bit unsigned immediate offset with scaling, the offset must be loaded into a register and the addressing mode is transformed to its
(reg, reg)form. Cranelift's addressing mode materialization currently usesx16as a scratch register to load the offset; even though both Cranelift and Winch usex16as a scratch register, its usage is not in sync, therefore clobbers can happen.This commit improves addressing modes by requiring early materialization of addressing modes into their respective Cranelift variants.
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Wasmtime GitHub notifications bot (Mar 03 2026 at 18:01):saulecabrera requested fitzgen for a review on PR #12708.
Wasmtime GitHub notifications bot (Mar 03 2026 at 18:01):saulecabrera requested wasmtime-compiler-reviewers for a review on PR #12708.
Wasmtime GitHub notifications bot (Mar 03 2026 at 18:01):saulecabrera requested wasmtime-core-reviewers for a review on PR #12708.
Wasmtime GitHub notifications bot (Mar 03 2026 at 18:05):saulecabrera submitted PR review.
Wasmtime GitHub notifications bot (Mar 03 2026 at 18:05):saulecabrera created PR review comment:
I removed this from the top-level
Addresssince it's only used here, which removes one level of indirection.
Wasmtime GitHub notifications bot (Mar 03 2026 at 20:51):github-actions[bot] added the label winch on PR #12708.
Wasmtime GitHub notifications bot (Mar 03 2026 at 20:52):github-actions[bot] commented on PR #12708:
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Last updated: Mar 23 2026 at 16:19 UTC